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RonFromOregon
01-12-2006, 05:36 AM
I have an antenna in my attic, which goes into my 5x8 multiswitch.

At my TV, I use a diplexer to get to the antenna signal. I see ATSC (OTA digital) but not NTSC (OTA analog). Is this normal? Is there an easy way to get the analog signals from my antenna down to my TV without running a new cable?

SleepyBob
01-12-2006, 07:04 AM
I have an antenna in my attic, which goes into my 5x8 multiswitch.

At my TV, I use a diplexer to get to the antenna signal. I see ATSC (OTA digital) but not NTSC (OTA analog). Is this normal? Is there an easy way to get the analog signals from my antenna down to my TV without running a new cable?

The diplexer shouldn't affect what stations come through, which makes me wonder:
1. Are you actually running the cable into your TV, or into your HR10-250, which only decodes ATSC?
2. Does your TV have both an ATSC and NTSC tuner, or just one?
3. Do you pick up the analog channels if you don't go through the diplexer?

rlj5242
01-12-2006, 07:04 AM
After the diplexer, are you splitting the antenna signal and sending one line to the HR10-250 and one to the TV? If it's just to the HR10, then you won't get NTSC since it does not have an NTSC tuner.

-Robert

RonFromOregon
01-12-2006, 05:43 PM
After the diplexer, I'm sending the ANT signal to a ReplayTV, which doesn't pick up anything. I also tried it with a little 5" b/w TV and still saw nothing.

Using a silver sensor antenna with the ReplayTV and 8" tv works fine.

JimSpence
01-13-2006, 09:44 AM
Splitting the antenna signal has reduced its strength. Try connecting the antenna output from the diplexer directly to the Replay and see what happens. Not all NTSC tuners are created equal.

RonFromOregon
01-13-2006, 12:04 PM
Try connecting the antenna output from the diplexer directly to the Replay and see what happens. Not all NTSC tuners are created equal.

I did that, same results. It really look like I'm getting ATSC but not NTSC. It possible that there's a filter somethere in the multiswitch, or the diplexer, that would filter out NTSC (analog) but leave ATSC (digital)?

JimSpence
01-13-2006, 01:00 PM
From the antenna, there is no difference in frequencies. It's how the frequency is used that differentiates analog and digital broadcasting.

Next test is to bypass the multiswitch and run a line directly to the receivers from the antenna.

And don't take this wrong, but you do know that your locals are using two different frequencies? One for their original analog and another for digital.

For example, in my area we have analog ch34 (ABC) which has terrible reception where I'm located. Yet the digital version locks in fine. The digital frequency is ch4. My HD receiver shows this as 34-1.